Machine for heading bolts



UNTTFQD STATES PATENT CFFTQE.

H. M. CLARK, OF NEW BRITAIN, CONNECTICUT.

MACHINE FOR HEADING- BOLTS.

Specication of Letters Patent No.

T0 all whom 'it may concern:

Be it known that I, HENRY M. CLARK, of New Britain, in the county of Hartford and State of Connecticut, have invented certain new and useful Improvements in Machinery for Heading Screws and Bolts; and I do hereby declare that the following is a full, clear, and exact description of the same, reference being had to the accompanying drawings, forming part of this specification, in which,-

Figure l, is a plan of a machine having all my improvements applied. Fig. 2, is a longitudinal vertical section of the same. Fig. 3, is a transverse vertical sectional view, showing certain of the working parts. Figs. 4, 5 and 6, are detail views of dierent parts of the machine.

Similar letters of reference indicate corresponding parts in the several figures.

To enable those skilled in the art to make and use my invention, I will proceed to describe its construction and operation.

A, is a strong bed-plate of cast iron supported by standards B, B, and carrying all the working parts of the machine.

C, is the main shaft of the machine supported in bearings a, a, set up on the bed plate and carrying a roller cam D, a pair of cams E, E, and other cams F, Gr, H, I, by which the various working parts of the machine are actuated.

J, J', are a pair of clamps which hold the blank during the heading operation, one of the said clamps being fixed and the other movable, the movable clamp J', being operated by a double toggle joint c, c which receives motion through a rod Z), from a horizontal slider K, which works in guides K', K', and is operated by the cam F, which rotates between two rollers 6l, d, attached to the side of the slider. The holding clamps receive the blanks at the top, where they are inserted, one at a time, by hand, when the clamps are open, the blank being supported until the clamps close upon it, partly by a pin c, which is attached to the under part of one clamp and enters a hole in the other, and partly, by a gage f, in front of the clamps. The blanks are all made of a certain length, and as soon as one is laid between the holding clamps, it is pushed forward to the upright lip 7", of the gage, to leave just a sufficient length protruding from the front end of the clamps to' form the head when upset, by means of a piston g,

14,086, dated January 15, 18156.

working through the rear end of the clamps, the said piston being fitted in a suitable fixed guide and being driven forward by a wedge h, working between a fixed cross head c', secured to the bed-plate and a sliding cross head j, attached to the piston, the said wedge being attached to, and moved by an elbow lever 7c, which is connected by a rod 71:, with the slider K. By driving the piston g, and the clamp j, both from the slider K, their simultaneous movement, which is necessary, 1s insured. The piston after the heading operation has been performed, is driven back by a spring which is coiled around it. The gage f, is not fixed, as it must be moved into its operative position and afterward moved out of the way, to enable the heading dies to come into operation, and for this purpose it is attached to an arm f', which vibrates transversely to the bolt. This is best shown in Fig. This armvis attached to the end of a lever Z, but as the duty of this lever can be better explained hereinafter, it will be at present only necessary to explain the movement of the arm, independently of the lever Z, as it is by this movement that the gage is moved into its operative position and then ont of the way of the heading dies. This movement is produced by the connection of the arm by a rod m, with an arm m', at one end of a horizontal rock-shaft L, at the opposite end of which is another arm m2, which carries a roller m3, which impinges against the face of the cam H.

The heading dies, which are best shown in Fig. 6, where the scale is larger than in the other figures, consist of an external forming die N, and an internal heading die n, attached to a piston n' working through the back of the external die. The dies shown are for the purpose of forming a bed screw head, that is to say, a square head with a collar, underneath it, as shown at Fig. 6, but dies for heads of other forms may be made on the same principle. The interior of the external die is the exact counterpart of the sides and collar (if it has a collar) of the intended head of the screw or bolt. The internal die or piston fits to the interior of the external die and the form of its end corresponds with the intended form of the top or crown of the head of the screw or bolt.

Two distinct movements are performed to produce the head. In the first of these movements the external and internal dies are stationary relatively to each other and move together toward the blank and soon as the end of the internal or upsetting die comes in contact with the end of the blank the upsetting action commencesI continuing until the fall of the external die has nearly come into contact with the ends of the holding clamps which are faced to form the under side of the head, by which time the blank has been sufficiently upset to nearly fill the forming dies; but it is found that by this movement alone, the corners of the head cannot be brought up sharp, and therefore a second movement is given to the internal die to make it advance'quicker than the forming die to upset the iron and spread it laterally sufficiently to fill the corners of the forming die.

The movements of the dies are effected in the following manner. The external or formingdie N, is secured to a horizontal slider O, which works in suitable ways on the bed plate, and the piston n, which carries the upsetting die works through this slider as far as an opening p, see Figs. l and 2, through which passes a short and strong lever g, working on a fulcrum g, which is secured to the slider. On the opposite side of the lever g, to the piston n', there is a bearing screw 1, which works in a fixed female screw in the slider; against this bearing screw the upper end of the lever rests during the greater part of the forward movement of the external forming die, and until the upsetting die is required to move in advance to produce the final upsetting. This latter movement is produced by the end of a screw s, which is fitted in the lower end of the lever, striking a cross piece s, of the framing and being arrested, by which the further movement of the slider O, is caused to make the upper end of the lever advance ,l and drive the piston forward faster than the slider. This double movement of the heading dies (N, 71,), it should be observed, is different to those arrangements wherein an internal die or presser (n) also is used to upset the blank and perfect the filling of the angles or corners of the main die, and upon such arrangements this portion of my invention is claimed as an improvement, in as much as there is no stoppage of the main die (N), or cooling of the iron, at the close of t-he main die stroke for the presser or internal die (n) to complete the work and perfect the filling of the corners, but both dies advance together to effect conjointly the upsetting and formation of the head, the internal die (n) only receiving a. quicker motion toward the close of the stroke of the two dies and both stop pressing or acting at the same time; thus, in a manner, one squeezer or presser effects both the upsetting, forming and filling, but it has the advantages of the two formers or pressers in the old arrangements referred to without their disadvantages either as regards bringing two separate cold-pressing surfaces in contact with the iron at different times or as regards abruptness which is detrimental to the easy working of the parts and their durability, the only abruptness which occurs here being when the inner die (n) receives its accelerated motion by the striking of the set screw (s) of the lever (g) against the projection (s), which sudden shock, not being a dead one as the two dies are even then in motion, has all the advantages of a blow over squeezing pressure in working on hot metal with the smoothness and ease of the latter.

The forward movement of the slider O, and dies to perform the heading operation, is producedv by the roller cam D, revolving against a toggle joint P, P, which connects the slider with the end of the framing, and tending to depress and straighten out the joint. The drawing back of the slider and dies after the heading operation, is performed by two curved rods t, Z, which connect the toggle joint with the axle a, of two rollers a, u, which rest on the top of the cams, E, E. As the roller cam D, rises from the toggle joint, the cams E, E, acting on the rollers u, u, raise the rods t, t, and thus, by raising and bending the toggle joint draw back the slider. In order to keep the rollers u', u, in place upon the cams E, E, their axle u', is connected by two vibrating arms, u2, u2,'with a standard us, set up on the bed plate.

In order to discharge the headed blank, if it should stick to the fixed clamp J, a sliding finger o, is arranged opposite the space between the clamps J, J', and heading dies, the said finger being driven toward the opening of the clamps to detach the blank by means of the cam I, acting through a lever I2, a rod T and a lever I3, as shown in Fig. 1. But if the blank should adhere to the movable clamp, it is detached by the motion given to the gage by the lever Z, which will now be described. The opposite end of the lever Z, to where the arm f, is attached, is connected by a rod Z, with one end of a lever R, the opposite end of which is depressed by every revolution of the cam G, so as to raise the rod Z and depress the arm f', to which the gage is att-ached. This depression of the arm f, takes place just before it is thrown into position by the rod m, to receive the blank preparatory to its being headed, and it is in its depressed condition that it receives the end of, and gages the position of the blank and it remains depressed until after it has moved aside to allow the heading dies to come into operation, but as soon as it has moved out of the way of the heading dies the prominent part of,

the cam G, passes the lever R, and allows stm the end of the said lever, where the rod Z-, is attached, to be pulled down by a spring Z2, and thereby causes the arm f, and the gage f, to be raised. The arm and gage remain raised until they have been moved by the arm m, between the heading dies and the clamps, and then are depressed by the action of the cam, the gage in being depressed knocking down the blank, which action of knocking down the blank has the effect of clearing the gage (f), by the tremor produced by such blow, of any adhering scale or dirt which in working on hot metals is apt to stick to the working part; and thus is the cleanliness and consequent eXactness of the gage (f) better preserved by making it (the gage) perform, by its peculiar operation, the double office of gage and striker to detach the bolt, and it also performs a further office of serving as a removable table to support the end of the blank before the clamps have grasped it and to move on one side when the heading process commences. Were it not for this gage performing the double office referred to a separate striker might be requisite to detach the bolt from the one clamp (J) as is provided, by the finger (fu), the other clamp and as is common to other machines.

All kinds of heads may be produced in this machine by making the dies of proper form. The depth of the head admits of variations without changing the dies by merely turning the screw 1*, back or forward to give the forming die a greater or less effective depth. The movement of the upsetting die n, to produce the final upsetting or finish the head is regulated so as to upset the iron just enough to bring the corners of the head up sharp, by adjusting the screw s, backward or forward.

What I claim as new and useful herein and desire to secure by Letters Patent is- 1. The arrangement herein shown and described of the two heading dies (N, n) when operating together in such a manner that while neither die is in motion nor at rest without a like action of the other, the one or internal heading die (n) receives an abrupt accelerated motion toward the close of the joint advance movement of the two dies, by means of the arrangement of the dies in the general slide (o) in combination with the lever (g), or its equivalent, acting in concert therewith essentially as and for the purpose set forth.

2. Giving to the gage (f) the several intermittent movements specified, upward7 downward and laterally, whereby, after performing its ofice of gaging, it moves away to give room for the heading dies to operate, and afterward suddenly descends to detach the bolt from the clamp, and by said action or blow to clear itself of any adhering scale or dirt as described.

H. M. CLARK.

Witnesses:

WM. G. Con, T. E. CASE. 

